#!/usr/bin/env ruby

# This test checks whether the packages create a dependency cycle.

require 'find'
require_relative '../lib/const'
require_relative '../lib/color'
require_relative '../lib/package'

@all_pkgs = {}

$LOAD_PATH.unshift '../lib'

puts "Running dependency cycle tests...\n".yellow

# Loads all packages
Dir['../packages/*.rb'].each do |filename|
  name = File.basename(filename, '.rb')
  pkg = Package.load_package(filename, name)
  @all_pkgs[name] = pkg
end

# Looking for cycles. @path will keep the current dependency path.
# @state will store :on_path for vertices on the current dependency path
# and :visited for vertices that have already been checked not to lead to
# cycles.
@failed = 0
@state = {}
@path = []
@uniq_path = []
def dfs(pkg)
  @path.push(pkg.name)
  if @state[pkg] == :on_path
    while @path.first != @path.last
      @path.shift
    end
    if not @uniq_path.include? @path.to_s and @path.to_s.include? ','
      @uniq_path.push(@path.to_s)
      @failed += 1
    end
  elsif @state[pkg] == nil
    @state[pkg] = :on_path
    if pkg.dependencies
      pkg.dependencies.each do |name, v|
        if name != pkg.name
          dfs(@all_pkgs[name])
        end
      end
    end
    @state[pkg] = :visited
  end
  @path.pop
end

# Calls dfs for every path
@all_pkgs.each do |name, pkg|
  dfs(pkg)
end

# Display dependency cycles
@uniq_path.sort.each do |path|
  puts path.lightred
end

@cycles = "cycles"
@cycles = "cycle" if @failed == 1

if @failed > 0
  abort "\n#{@failed} dependency #{@cycles} found.".lightred
else
  puts "\nNo dependency cycles found.".lightgreen
end